One of the major challenges of wireless networks, such as cellular networks, is in-building coverage. Wireless antennas are typically located outside buildings, while in many cases the users are located inside the buildings. As a result, the wireless signals have to penetrate the walls of the buildings. While penetrating the walls, the signal is attenuated, causing degradation of the communication quality.
This challenge of in-building coverage is well known and there are some methods to address this challenge, mainly repeaters and in-building Distributed Antenna Systems (DAS). Both methods are typically used for highly populated locations, such as office buildings, public buildings, shopping centers and campuses.
Now a brief overview of PON architecture will be provided. A PON is an access network based on optical fibers. The network is built as a Point to Multi-point network, where a single optical interface, known as Optical Line Terminal (OLT), is located at the Central Office (CO) or Head-End (HE) and serves multiple users (typically 16 to 64 users). The OLT is connected via optical fiber (usually called feeder) to a passive splitter, which splits the optical signal among multiple optical fibers (usually called distribution lines or drops). The passive splitter may be located at the CO (centralized split) or at a passive cabinet in the field (distributed split). The distribution lines (or drops) terminate with an Optical Network Unit (ONU) which converts the optical signals to electrical signals. The ONU may be located at the subscriber's home (AKA FTTH—Fiber To The Home), at the subscriber's building (AKA FTTB) where the electrical signals are forwarded to the end users using the building's infrastructure (e.g. CAT 5) or at the curb (AKA FTTC) where the electrical signals are forwarded to the end users using copper wires (e.g. DSL). There are several flavors of PON, such as APON, BPON, EPON, GPON and GePON. All flavors share the same basic architecture of passive splitting and differ from each other by the data rate and the protocols. FIG. 1 illustrates a typical PON.
There is a need for improved in-building coverage for wireless communications such as cell phones, but no prior solution has effectively taken advantage of the possibilities of employing the PON architecture in this regard.